A reader at respected airline industry site Leeham News offered a comment that suggests they have access to Boeing’s internal quality control systems, and shares details of what they saw regarding the Boeing 737 MAX 9 flown by Alaska Airlines that had a door plug detach inflight, causing rapid decompression of the aircraft.
The takeaway appears to be that outsourced plane components have so many problems when they show up at the production line that Boeing’s quality control staff can’t keep up with them all.
Current Boeing employee here – I will save you waiting two years for the NTSB report to come out and give it to you for free: the reason the door blew off is stated in black and white in Boeings own records. It is also very, very stupid and speaks volumes about the quality culture at certain portions of the business.
…With that out of the way… why did the left hand (LH) mid-exit door plug blow off of the 737-9 registered as N704AL? Simple- as has been covered in a number of articles and videos across aviation channels, there are 4 bolts that prevent the mid-exit door plug from sliding up off of the door stop fittings that take the actual pressurization loads in flight, and these 4 bolts were not installed when Boeing delivered the airplane, our own records reflect this.
…As a result, this check job that should find minimal defects has in the past 365 calendar days recorded 392 nonconforming findings on 737 mid fuselage door installations (so both actual doors for the high density configs, and plugs like the one that blew out). That is a hideously high and very alarming number, and if our quality system on 737 was healthy, it would have stopped the line and driven the issue back to supplier after the first few instances.
…Now, on the incident aircraft this check job was completed on 31 August 2023, and did turn up discrepancies, but on the RH side door, not the LH that actually failed. I could blame the team for missing certain details, but given the enormous volume of defects they were already finding and fixing, it was inevitable something would slip through- and on the incident aircraft something did. I know what you are thinking at this point, but grab some popcorn because there is a plot twist coming up.
The next day on 1 September 2023 a different team (remember 737s flow through the factory quite quickly, 24 hours completely changes who is working on the plane) wrote up a finding for damaged and improperly installed rivets on the LH mid-exit door of the incident aircraft.
…Because there are so many problems with the Spirit build in the 737, Spirit has teams on site in Renton performing warranty work for all of their shoddy quality, and this SAT promptly gets shunted into their queue as a warranty item. Lots of bickering ensues in the SAT messages, and it takes a bit for Spirit to get to the work package. Once they have finished, they send it back to a Boeing QA for final acceptance, but then Malicious Stupid Happens! The Boeing QA writes another record in CMES (again, the correct venue) stating (with pictures) that Spirit has not actually reworked the discrepant rivets, they *just painted over the defects*. In Boeing production speak, this is a “process failure”. For an A&P mechanic at an airline, this would be called “federal crime”.
…finally we get to the damning entry which reads something along the lines of “coordinating with the doors team to determine if the door will have to be removed entirely, or just opened. If it is removed then a Removal will have to be written.” Note: a Removal is a type of record in CMES that requires formal sign off from QA that the airplane been restored to drawing requirements.
If you have been paying attention to this situation closely, you may be able to spot the critical error: regardless of whether the door is simply opened or removed entirely, the 4 retaining bolts that keep it from sliding off of the door stops have to be pulled out. A removal should be written in either case for QA to verify install, but as it turns out, someone (exactly who will be a fun question for investigators) decides that the door only needs to be opened, and no formal Removal is generated in CMES (the reason for which is unclear, and a major process failure). Therefore, in the official build records of the airplane, a pressure seal that cannot be accessed without opening the door (and thereby removing retaining bolts) is documented as being replaced, but the door is never officially opened and thus no QA inspection is required.
The commenter concludes, “Where are the bolts? Probably sitting forgotten and unlabeled (because there is no formal record number to label them with) on a work-in-progress bench, unless someone already tossed them in the scrap bin to tidy up.”
The information was first flagged by aviation watchdog JonNYC.
..unvetted (every other synonym for that as well,) commenter here:https://t.co/R3KdqDHION
And now I'm seeing a couple other usually credible, usually careful folks positing same idea.
As always– more so than usual– no idea myself.
— JonNYC (@xJonNYC) January 22, 2024
Boeing outsources a lot of the production of components for its aircraft because it’s cheaper as part of an overall shift in strategy that dates to CEO Harry Stonecipher who had been CEO of McDonnell Douglas,
When people say I changed the culture of Boeing, that was the intent, so that it’s run like a business rather than a great engineering firm.
One of the major suppliers is Spirit AeroSystems, which used to be part of Boeing and was spun out and sold to private equity in 2005. That’s whose work is at issue here.
This story suggests a one-off mistake with this particular part on this particular aircraft, though also that production issues are common. That doesn’t square with a theory that bolts could have come loose from flying a poorly-designed aircraft, or that Boeing 737-900ERs are being inspected too. Those have the same door plug because the MAX 9 is built on the same airframe. It may or may not square with finding loose door plugs on other Boeing 737 MAX 9s.
So this story is far from ‘official’ but it seems knowledgeable from someone who suggests they’re a whistleblower inside of Boeing. A story in Politico this morning suggests that Boeing’s new team of lobbyists has their work cut out for them. It certainly appears so, but perhaps work needs to start at the board and C-suite level.
The ‘bolts not there altogether’ theory gains traction
Leaving Boeing aside I suppose it could have been ‘worse’ for the airline customers – a design flaw like some interference with the weight of the engines and the flex of the fuselage could have left the whole fleet in question for years even after a litany of inspections.
Not that checking QA flaws from the factory is any picnic.
Occam’s razor? Given that:
1. this was a relatively new aircraft which gave warning signs on multiple occasions before the catastrophic failure, and
2. that other aircraft with identical/similar door plugs on the same family of aircraft have been flying without incident for years,
the explanation that the bolts were not installed during the production process is certainly credible and, perhaps, probable.
Two things
1) I live in the Seattle area and have several close friends that were Boeing engineers, each with 15+ years of experience. They cashed out and retired at the end of last year because Boeing changed their retirement plan from a pension to a 401k. The difference was in “the millions”.
Net result, The retirement plan change saved Boeing money at the cost of A LOT of brain power and engineering talent leaving Boeing.
2) I bounced the above report off two friends currently at Boeing. One in the quality improvement area, another manuf. engineering. They both say that the report “rings true” and uses certain terms the right way.
“392 nonconforming findings on 737 mid fuselage door installations” – Are you kidding me?
Boeing cost cutting, it’s getting VERY expensive!
A change in C-Suite level management & boardroom should’ve been obvious after the pair of 737-8 MAX crashed, if it wasn’t already pretty clear by the time (Mc)Boeing bungled the C-Series with its ill advised, colossally stupid & abjectly failed attempted trade-war with Canada in 2017.
I’ve said it many times before, but it’s worth repeating:
Expecting the same idiots that destroyed the company to “fix it” is a fool’s errand.
Hasn’t this already been proved – many times over – by now?
And yet, here we are.
If correct this explains why there was no inspection but doesn’t explain why whoever did the work didn’t reinstall the bolts, which is even more troubling.
As an engineer it’s hard to imagine someone being allowed to work on something without knowing the process. Perhaps those involved thought the work on the door was ongoing in which case it wouldn’t make sense to install the bolts until everything was done when someone would take care of it. Shift change comes along, it’s a new group of people, the door is shut so it looks done, the paperwork isn’t clear or they ignore it and then there is no inspection.
Regardless of the cause it’s an inexcusable failure of process.
This being the internet, it is hard to know what to believe in this situation.
WHERE IS YOUR UNION? THIS IS A GOOD ARGUMENT FOR YOUR UNION TO FIGHT TO STOP OUTSOURCING YOUR WORK! I have witnessed first hand in aerospace where work is outsourced and people don’t speak up until the work is gone! Many contracts have clauses that offer the Union to argue moving Union work, USE IT, OR LOOSE IT!
@jns re: hard to believe in this situation……
welp, there’s a hole in the bird and a door on the ground
i would put my money on Joe Patroni
@Ken D
You do realize that Spirit Aerosystems is represented by the IAM union.
Don’t forget that Spirit AeroSystems also makes parts (like wings) for AirBus! Maybe AirBus catches more of their errors, but Boeing is not alone in outsourcing, and not alone in outsourcing to Spirit AeroSystems.
@Howard they did change out most of the C suite including CEO and head of commercial airplanes after the Max 8 issues. Calhoun joined in 2020.
Wow,
This is terrifying. It also seems quite emblematic of manufacturing in the United States these days: reduce costs to the maximum, even if there are quality issues. We see this in healthcare, we see this in automobile manufacturing, we see it in Boeing.
Until this unhealthy obsession with absolute maximization of financial return goes away, this will not get better.
H2oman
You do realize the plug was manufactured in Malaysia. Read before you going spouting off and sound like an ignorant a**
OK, I believe that 4 bolts were not installed. But how many other Spirit components are on these planes that either have defects or are not installed properly? It is a bit scary to contemplate if these planes are ticking time bombs beyond this door issue.
@JSmith
You really should learn to read. BOLT. Look it up on dictionary.com because obviously you glossed over it cause you did not understand it.. The issue is the bolts. Not the door itself. Doors need attachments. If you don’t it understand that, well, I guess it is a good thing you live in the US where stupid people are protected so well they can still live …
The NTSB will say at least two things:
1) The bolts were not is talked.
2) It as an abjectly negligent design failure that the inaccessible doors (I’m not calling them plugs anymore because they are not) are designed, in their normal operating state, TO OPEN THEMSELVES! (to make it easy for them to stay open during maintence.)
The pins and guides are reversed from normal plane doors so that the inaccessible doors open UP.
And you’d think, we’ll that’s good, because then gravity would hold them down! But:
1) No, not in turbulence, when air puts a ton of force on the plane pushing it down, and none of that force is acting directly on the door,
And 2, most egregiously,
BOEING PUT SPRINGS ON THE BOTTOM HINGES TO CONSTANTLY PUSH THE DOOR UP AND OPEN! (again, to make it easier to jeep the door open during maintenence.)
The only thing that keeps these inaccessible doors closed is the bolts and a weeee bit of friction.
That single point of failure (the bolts) is entirely unacceptable in modern airplane design based on redundancy.
@Greg: I rhink they have to ground all the max-9s with the inaccessible doors until they are reenfineered to fail-safe-closed when at altitude.
All the accessible (regular) doors, if there is ANY failure, or ALL the failures, at altitude, it stays closed.
Boeng designed the doors so that if there are failures at altitude, they OPEN!
@Ken D: Unfortunately, this isn’t good for the union. The failure happened entirely at Boeing. Boeing designed a door that opens in mid-flight, and it was at Boeing that the bolts didn’t get installed. 100 percent a Boeing problem.
Obviously if the bolts had been installed, things would be fine. And if the door had been designed to STAY CLOSED things would have been fine.
As in almost all things aircraft failure related, more than one failure was required, but they were Boeing failures.
This is lunatic fringe behavior. It must be stopped dead its tracks. All Boeing production needs to come to an immediate halt. The NTSB and Transportation head, Buttigive, must order such until Boeing pays thousands of independent inspectors to go thru every nut, bolt, wiring schematic versus actual wiring, engine mounts, window and door seals, cargo hold doors and seals, and all redundant systems tests to ensure actual viability instead of simple, proclaimed presence. Boeing needs to fully fund independent oversight of their builds including manufacturing at Spirit over the next two decades at a minimum. All inspectors need to be retired, old guys. No joke. Huge fines also need be assessed to both companies for their wanton disregard for adherence to standard engineering concepts that include excesses in tolerances to ensure safety. All fines collected should be placed in interest bearing notes of 5yr min terms to pay future compensation for deaths and injuries for which Boeing and Spirit will assuredly be responsible. Many crashes to come. Accountants are the bane of every industry that relies on quality. In the airline industry, accountants are 3rd degree murderers (with intentional, depraved indifference).
This is a new comment in response to new comments exposing new information. This is not a duplicate comment. This is lunatic fringe behavior. It must be stopped dead its tracks. All Boeing production needs to come to an immediate halt. The NTSB and Transportation head, Buttigive, must order such until Boeing pays thousands of independent inspectors to go thru every nut, bolt, wiring schematic versus actual wiring, engine mounts, window and door seals, cargo hold doors and seals, and all redundant systems tests to ensure actual viability instead of simple, proclaimed presence. Boeing needs to fully fund independent oversight of their builds including manufacturing at Spirit over the next two decades at a minimum. All inspectors need to be retired, old guys. No joke. Huge fines also need be assessed to both companies for their wanton disregard for adherence to standard engineering concepts that include excesses in tolerances to ensure safety. All fines collected should be placed in interest bearing notes of 5yr min terms to pay future compensation for deaths and injuries for which Boeing and Spirit will assuredly be responsible. Many crashes to come. Accountants are the bane of every industry that relies on quality. In the airline industry, accountants are 3rd degree murderers (with intentional, depraved indifference).
Everyone: Closed doors should stay closed.
Boeing: But what if it’s REALLY IMPORTANT that they stay closed?
Profits over safety. I do t think many people are still saying if it ain’t a Boeing I ain’t going anymore. Boring has forgotten that quality equals profits.
4 bolts to hold in the plug is Boeing over design, any one bolt would hold the plug in place. Sadly it’s not possible for this to happen even if the bolts came loose.
Total lack of real Quality.
This is the difference between QC and QA.
If it’s a Boeing,
I’m not going
this site requires any comment to have a registered account so they can spam you. even though as boeing engineer of 35 years, you will not see my comment here.
@KenD,
Boeing has bullied its unions to submission. The IAM especially had to bow down to the company after the 2008 strike. Those factories were run on fear, and the company played some very dirty tactics. For example, moving the 787 production to the Carolinas.
The morale at Boeing and Spirit is rock bottom. Boeing ultimately plans to have everything outsourced and the planes put together at the end by China. The only thing the company would do at that point is slap a “Boeing” sticker on the plane.
Sadly, the Executives and Management at Boeing still have not learned any lessons from this. Most companies would have had their entire leadership heads rolling from something like this. But, they will continue to cover up, clean up, and proceed to their ultimate goal at the end. By 2040-2050, very little production of Boeing planes will be done by Boeing employees. The leadership team has a goal, and a date set to ensure this “project” is completed. At the same time, I have doubts Boeing will be around by that time if it continues down this dangerous path. Cheap and airplanes are the worst possible combination I can think of. But!! Make no mistake about it, the Board Of Directors and management haven’t learned a thing from this. I doubt this will be the last of the MAX debacle.
The whistleblower stated that “If this was an A&P Mechanic, it’d be a federal crime”. It’s a great point, because anyone who maintains aircraft in the USA is a federally licensed Aircraft Maintenance Technician, ie Airframe & Powerplant Mechanic. To be a license holder, they must either attend an FAA approved educational program via a university, community college, vocational-technical school, or verify work experience usually gained from the military before passing a rigorous set of oral and practical exams.
In the 80’s and 90’s, I worked at the Boeing Everett factory installing engines on the 747-400. I possessed, and currently possess, an A&P License. An extremely small minority of us in the factory had A&P’s. Boeing hires hamburger flippers…literally. They put them through a short training program and onto the factory floor they go as “Assembler/Installers”, with little to zero experience in aviation, and no federally mandated license. Don’t get me wrong, there were many, many, many great and passionate employees putting together wonderful aircraft there as factory workers in those days, and I can assure you there still are. However, when the FAA began mandating random drug testing in 1990, if you didn’t work on the flight line with an A&P, you weren’t subjected to drug tests. Needless to say, half the factory back in the late 80’s/early 90’s were either pot and/or coke heads. The FAA drug testing laws still don’t apply to factory workers, as they’re non-license holders. Boeing never had a random drug testing policy back in the day, and I’m unsure if they do now. But, with the recreational marijuana laws in Washington State, I doubt it….they’d lose half their employees.
Not an engineer but trained in management . It has got to be clear at this point that the culture that destroyed McDonnel Douglas is now doing the same to Boeing. Is the Board at Boeing so blind and incompetent that it doesn’t understand the problem begins with them? Hiring an accountant as the new CEO just reinforces their willingness to wear blinders and continue down the same road with minimal changes. IF the quality control on the 737 9 max is as bad as this report indicates and is being used throughout then any customer should be wary of any Boeing product.
@Tim Thomas – huh?
With all of the comments from the hate Boeing first crowd taken together, I am surprised that 100% of their airplanes made in the last 10 years didn’t immediately fall out of the sky upon takeoff the first time.
I think we should buy planes ‘Made in China’, like everything else they make for us. They’ll probably do a better job. .
I will not fly 10 to 12 hours. In a Boeing. I will advise my children. Not to set one foot in these A/C. . Do you think this child, that had his shirt riped off. Will EVER FLY again. ? I bet Not! Everyone on this flight. I hope you win every law sute!
The Europeans, even the Chinese, are more into quality control. Let them build our Boeing planes. Or sell us their Airbus. And C919.
Counterpoint —
If it was a manufacturing problem, how did the bird survive so many cycles?
Now, I see the point (and mostly agree with it) but this detail is not sufficiently addressed anywhere.
“WHISTLE BLOWERS” pop up AFTER THE FACT to say “I told you so” or “this happens all the time” etc… I am always suspect of such egregious information. If all of what he said is true than I can’t understand why he came out to accuse Boeing & it’s suppliers of being so bad that they are passing off such deadly aircraft to the airlines.
From physics/engineering it seems if one assumes the bolts were not installed then at 16000 ft altitude what pressure was on the door? Use the area of door plug to find the force. Then compare this with the 12 distributed fasteners (I read somewhere else that 12 fasteners and 4 bolts used to install door plug) against their rated max. Force before failure. If greater, then the fasteners fail and the door plug detaches. End of story the bolts were not installed. If 4 bolts were installed correctly then the door plug should have remained secured. Otherwise, if the failure still happened, then there is a major design issue. It seems rather simple maybe to simple but independent of QC deductions/speculations.
Sadly, I’m not optimistic for the future. It’s clear that Boeing is “too big too fail” i.e. U.S. government requires them to exist regardless. Of course C-suite knows and loves this the pigs at the slough they are. Great for them, they’ll get a parachute package into paradise. Hey, maybe they might get caught up in an avalanche at Aspen. You can only dream.
When I worked for Boeing any fasteners that were removed were trashed and replaced with new fasteners. I no longer work at Boeing. The problem I’ve experienced in aerospace is these suppliers do not value hands on experience! Take up an issue to the manager (the one fresh out of college with a degree and no manufacturing experience) show them the specifications on THEIR computer and they ask if your being too picky? Boeing incoming inspectors should know that titanium weld assemblies should not be wire brushed nor sandblasted, That is a clear indication that the titanium was not purged per specifications. Personally I have seen many retire taking their experience with them.
@FlyOften:
The door is attached by two hinges at the bottom, and two at the top. It also has 12 small “fasteners”, and two pin-and-groove channels towards the top, with the pins on the plane fuselage and the grooves on the door. When the door is closed, the grooves slide onto the pins and then the door slides down onto the pins so they are at the top of the grooves. This aligns the 12 ‘fasteners’, which are just metal flanges on the side of the door that match flanges on the fuselage.
It’s these fasteners that keep the door from opening – if the door is fully closed.
But if the door rides up so that the fasteners are no longer aligned, there is nothing keeping the door closed.
Key piece of information: The bottom hinges on the fake door are SPRING LOADED to PUSH THE DOOR OPEN! The bolts prevent the springs from doing that. No bolts, nothing preventing the door from opening except a little bit of friction between the fasteners.
So, out of the factory, the door is fully closed, with hinges exerting a constant upward force to open the door that is a bit less than the friction of the fasteners against each other.
When there’s vibrations, or turbulence, or maybe frame flexing, that force PLUS the upward force of the springs is enough to push the door a tiny bit more open. But that force against the upward force of the springs doesn’t push the door more closed..
So over time, the door every more slowly gets a bit more open.
Or maybe there was just extreme turbulence for the first time on this particular flight.
Either way, the door slid itself up so the fasteners were no longer aligned, then the now open door blew out.
Decades ago Aerospace used to promote from the floor, Those who chose to move into management positions could show anyone how to do any job! Now we have managers and engineers with zero hands on manufacturing experience and no respect for experience!
Change is desperately needed at the highest levels of Boeing. The people on the business end of the company, the ones pushing for greater/faster through-put turn a blind-eye to corner cutting thinking it will speed things up. And here we are, production not just slowed down but at a complete standstill. How efficient is that??
As an AME who worked for 50 years on Boeing aircraft and flew on them as a flying mech this really scares me. I have MAX license and have flown many miles on them for work. What bothers me about ALL the MAX aircraft is what don’t we know. What else is not done properly?
Very glad I retired and can now choose what I fly on. Likely won’t be a MAX of any model.
Since Douglas merger the goal is to liquidate commercial and focus on defense cost plus. This move to lobbying central DC. To goose their stock options massive cost cuts, outsourcing and no new designs. Within a decade Boeing will either seek federal assistance or be out of commercial
As the 737-7,8,9 have the CFM56-7B27 engine with 27,300 lbs thrust, Boeing engineers could attempt a re-fit of One (1) 737 -900 Max as a test-bed for the SNECMA engine ( and Originall pylon ), and lighten the aircraft from its MTOW of 187,700 lbs down to the older 737 MTOW of 172,500 lbs. Remove two or three rows of seats, lighten the fuel load, etc. This would sideline the ‘monster’ LEAP engine & pylon, and use the Original 737 FMS. The plane won’t need above-wing speed brakes ( Flight Control software ) to hold the nose down at climbout. The Max would essentially be a 737-900ER upgrade.
I work in aircraft, the FAA is not that great at catching things in an audit and management knows it. It really seems like the only way these kinds of issues get addressed is when there is an incident.
I just retired from Boeing after building Wings at Boeing with 18 years experience. I can at least say this story for sure points the finger in most likely the right direction. CMES is incredibly complicated, esspecially for the amount of new hires working in both production and QA right now. (My swing shift shop had over 80% new hires) Let’s not forget this all happened (yes this actually happened during SPIRIT AERO’S eyebrowed hole debacle) while Mechanics and Inspectors BOTH HAD ZERO TO DO WHILE SITTING ON THEIR BUTTS FOR 8 HOURS A DAY PRETTY MUCH HALF OF ALL OF SEPT AND OCT. This was not good for new hires trying to learn a job. Also: all of the Diverity hires they’ve done hasn’t helped anything. Look at the general skin tone at Boeing nowadays on the factory floor…I’m not being racist, I’m just saying look at the demographics of who is actually working at Boeing right now. Previous related job experience is no longer needed to build airplanes. Boeing needs to slow down the rate at which it ramps up production…I get why they do it (for shareholder value) but, what I’m seeing is that this is (and always has been) cheating the system in building planes safe. I’m also a stock holder and know to that even though this never should happen shows it can and will and did happen given the methods Boeing uses today. NOBODY REALLY LIKES TO WORK THE WEEKEND…just greedy Mechanics and that is half the reason…if everyone had a reasonable amount of work to accomplish in 8 hours, this problem would take care of itself. Plus I just think too Boeing is having severe growing pains right now.
Disgusting. Steer me to my next A380 flight.
Whenever private equity enters the picture I would be suspicious on any of their work since they emphasize short term results over anything else.
@T
https://youtu.be/IaWdEtANi-0?si=KaGZ95Pn-i-cTL1F
https://youtu.be/rvkEpstd9os?si=zPUzW1U8B95ojNhm